NEW YORK (Reuters Health) - Intermittent episodes of detectable viremia in patients with well-controlled HIV infection represent random biological and statistical variation, and may not be associated with new drug resistance mutations, investigators report.
“These results should provide relief to hundreds of thousands of HIV-positive patients in the United States currently taking drug therapy...and reassure them that their medications have not failed,” principal investigator Dr. Robert F. Siliciano, a physician at Johns Hopkins University School of Medicine in Baltimore, said in a University statement.
Dr. Siliciano and his associates prospectively followed 10 patients receiving HAART who had achieved suppression of viremia to below 50 copies/mL. Blood samples were drawn every 2 to 3 days for 3 to 4 months to check for viral load, drug levels and drug resistant mutations.
A total of 18 blips occurred in 9 patients, lasting a median of 2.5 days, they report the February 16th issue of the Journal of the American Medical Association. Median magnitude of the blips was 79 copies/mL (maximum 201 copies/mL), which is “consistent with random variation around a mean level of 10 to 20 copies/mL,” the authors note. Seventy-eight percent occurred when drug levels were above suggested trough concentrations.
Blips were not associated with demographic, clinical or therapeutic parameters, such as CD4 count, number of drugs in the current regimen, intercurrent illnesses or vaccinations. According to the investigators, the only factor for which there was a marginal association (p = 0.08) was patient-reported adherence.
The authors observed no new drug resistance mutations, either during or immediately after blips, suggesting that blips do not lead to resistance and “raising concerns about the usefulness of therapeutic drug monitoring in the management of patients experiencing blips.”
While concluding that viral blips may not be cause for clinical concern, Dr. Siliciano’s group also notes that “blips with a magnitude of greater than 200 copies/mL or blips that are detected in at least two independent or consecutive measurements may be more of a cause for concern.”
Source: JAMA 2005;293:817-829. [ Google search on this article ]
MeSH Headings:Biological Phenomena: Biological Phenomena, Cell Phenomena, and Immunity: Biological Sciences: Biology: Drug Resistance, Microbial: Genetics: Genetics, Microbial: Health Occupations: Microbiologic Phenomena: Microbiological Techniques: Investigative Techniques: Pharmacogenetics: Technology: Technology, Industry, and Agriculture: Technology, Medical: Allied Health Occupations: Viral Load: Analytical, Diagnostic and Therapeutic Techniques and Equipment: Biological Sciences: Technology, Food and BeveragesCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
